The effectiveness of the mesoporous TiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> layer, which acts as an active n-type semiconductor layer in dye-sensitized solar cells (DSSCs), was investigated by varying AgVO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> doping. To optimize the meso-superstructure, the doping concentration was varied from 0% to 25% using experimentally validated simulations. Moreover, performance comparisons between the experimentally fabricated DSSCs based on natural beetroot dye and the commonly used N719 dye were made. A 15% doping concentration was found optimum for our DSSC, which delivered an output power of 19.24 mW, 6.1% power conversion efficiency, and an open-circuit voltage, <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${V}_{\text {oc}}$ </tex-math></inline-formula> , of 0.5 V and a short-circuit current density, <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${J}_{\text {sc}}$ </tex-math></inline-formula> , of 21 mA/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> in diffused light conditions. Based on these performance results, we integrated our optimized DSSC in an underwater sensing unit as a light harvester.